This disclosure generally relates to a deployment mechanism for a ram air turbine. More particularly, this disclosure relates to a deployment mechanism that includes features that prevent storage of the ram air turbine when the turbine is not in a desired orientation.
A ram air turbine is used to generate supplemental power in an aircraft by extracting power from an air stream proximate the exterior of the aircraft during flight. The ram air turbine includes a turbine that drives an electric motor or hydraulic pump that is suspended on a strut assembly. In operation, the turbine is moved outward from the airplane to a position that provides clearance between blades of the turbine and the aircraft. A release mechanism prevents rotation of the blades until the turbine is sufficiently clear of the aircraft. Storage of the ram air turbine after use requires that the blades be again locked in a position that does not allow contact with the exterior surface or door of the aircraft. Confirmation that the blades are locked and in a stowable orientation is conventionally indicated by electronic sensors that sense a position of a release mechanism. The use of electronic sensors increases programming burdens and requires time consuming calibration and maintenance.